A Cabinet minister has admitted that trade talks with the European Union are in a “difficult phase” after Government sources suggested hopes of a deal were diminishing.

Business Secretary Alok Sharma said there were “a number of tricky issues” still outstanding, but stressed that the UK negotiating team was working hard to seal a deal.

His remarks came as reports suggested Michel Barnier, the EU’s chief negotiator, would remain in London to continue talks over the weekend, having initially planned to travel back to Brussels on Friday.

The European Commission would not confirm Mr Barnier’s weekend travel plans and said only that a “full day of negotiations” was expected on Friday.

Negotiations between the UK and EU were said to be showing promise this week but then seemed to stall on Thursday, with Britain claiming Brussels was calling for fresh concessions at the 11th hour.

A senior Government source said: “A breakthrough is still possible in the next few days but that prospect is receding.”

With the Brexit transition period due to end on December 31, there is little time to get a deal agreed by negotiators and approved by the EU’s leaders, Westminster and the European Parliament.

Mr Sharma, speaking to BBC Breakfast, confirmed that gaps remained between the two sides.

Fishing and the so-called “level playing field” aimed at preventing unfair competition on state subsidies and standards remain the main issues to be resolved in the talks.

“We are committed to reaching an agreement with the EU on this particular discussion that we are having,” he said.

“But, of course, time is short and we are in a difficult phase. There’s no denying that. There are a number of tricky issues that still have to be resolved.”

Mr Sharma said Lord Frost, the UK’s chief negotiator, and his team were “working incredibly hard” and “in good faith” to get a deal over the line.

“Let’s see where we get to,” he added.

European Commission spokesman Eric Mamer, asked for an update on fishing rights, told reporters in Brussels: “Today is still a day for negotiations, they are ongoing, so we can’t make any comments on the contents of what is being discussed.”

The publicly-aired Brussels and Westminster tensions came after Ireland’s foreign minister Simon Coveney said there was a “good chance” of a trade deal on Thursday.

Lord Frost
The UK’s chief Brexit negotiator, Lord Frost (Dominic Lipinski/PA)

Meanwhile, Prime Minister Boris Johnson will press ahead with plans allowing ministers to tear up the Brexit divorce deal he has already agreed, despite the current round of UK-EU talks being at a critical stage.

The Government will ask MPs to reinstate controversial legislation giving ministers the power to break international law by ignoring provisions in the Withdrawal Agreement relating to Northern Ireland.

The Commons will vote on the UK Internal Market Bill on Monday, potentially throwing the talks on a UK-European Union trade deal into deep crisis unless an agreement can be reached by then.

MPs will be asked to reinsert the controversial Northern Ireland provisions into the UK Internal Market Bill after the Lords voted to remove them.

The EU has already taken the first steps towards legal action over the legislation.

The Government will also introduce the Taxation (Post-Transition Period) Bill, which reportedly includes measures to override parts of the divorce deal struck by the Prime Minister and the EU in 2019.